Scott “Big Red” Farrell wasn’t sure he approved of the costumes on a recent Saturday night at a club in San Francisco’s Potrero Hill: Hoodies, slacks, t-shirts and nylon satchels with startup brand names on them.

“It’s a real professional crowd,” he said, surveying the room, in a bemused tone. “Real professional.”

At any of the many tech mixers that take place on any given night of the week in the geek capital of the world, this might have been perfectly fine attire. But not at Mission Control, a members-only sex club and community, which has been operating successfully and quietly for a dozen years, most of the time in a grand 3,500-square-foot apartment nearby.

This is a new space, for lots of reasons, including that over the last two years, membership has ballooned to more than 500 people. The founder, Polly “Superstar” Whittaker, a longtime leader in the city’s famously progressive and open sex subcultures, said she’s been happily surprised by a growing demographic: Tech workers.

Some people might suggest that Mission Control’s popularity now isn’t about technologists being inherently drawn to sex clubs, but just a reflection of who’s exploring the city these days. That would be techies, whose companies are locating here in increasing number, creating both tensions and opportunities.

“I don’t think it’s necessarily tech and polyamory overlapping. It’s more about who’s young and single in the city right now,” said Liz, a 26-year-old data scientist, who has become active in Mission Control leadership and, like many, did not want her full name used. “And there are overlaps with class and education and who has time to do things like this.”

In other words, hoodie-wearing aside, techies have flooded the social scene in San Francisco as never before, as the sector has moved north from Silicon Valley.

“Mission Control is a space for all the different types in San Francisco. Normal people need a place to f— too, not just the freaks,” said Superstar, in an earlier interview. “We started Club Kiss parties for these buttoned-up tech types. Now it’s our most popular night.”

It’s not just a visit for a weird night out either, it seems, with some becoming leaders within the free-wheeling scene. Google employees are planning some of Mission Control’s parties, for example. And startup co-founders swing by together after a long day at the co-working office.

The long-time participants at Mission Control, who see their volunteer-run themed nights as a sort of public service, seem excited by the newcomers. And though, by all means, not every tech worker goes to Mission Control (and, in turn, not every Mission Control party is overrun with techies), it’s an interesting instance of two cultures mixing.

“There’s been programmers and people in the tech industry involved since we started. There’s a correlation between intelligent nerdy people and open ideas about relationships,” said Jason James, who is Mission Control’s longtime “captain,” in an earlier interview. “It just seems to make sense to a lot of people who are in technology.”

He added, referring to a different time in San Francisco’s hippie history, compared to its current hipster one: “The time and place that we’re in right now, it’s kind of our own summer of love.”

Nellie Bowles

No surprise, then, that the night after Valentine’s Day was the group’s largest party yet, with more than 350 people packed into that two-story warehouse on Potrero Hill. On the first floor, in low lighting, there was a BYOB bar with a row of wine bottles and a platter of chocolates. People milled on the dance floor, shaking hands with new friends. For fun, there was a photo booth set up in back.

David, a 31-year-old tech startup founder with a Ph.D. in neuroscience, stood bare-chested by the bar. A young woman smiled at him and whispered something, he said yes, and she popped her head down to lick his abs.

“You can lick them, too, before you ask any questions,” he said to me. His kind offer was declined, but David needed no prompting to wax on about the larger concepts and motivations he sees at play at Mission Control for the digerati.

“They say there’s an app for everything: I have an app for groceries, an app for laundry. Apps are built by people who take a mundane part of life and make it better. Here, this is that same creative mentality,” he said. “People in tech startups are open-minded, they’re seeking out different experiences, endless possibilities.”

He added, as if he were talking about the intricacies of programming a photo-sharing app: “It’s professional people who are creating awesome things during the day, and they like to party at night.”

Megan, a 24-year-old project manager who said she worked at a startup, wore a white silk blouse tucked into a tight pencil skirt. Like many, she declined to give her last name or her company (too easy to identify), but she did not mind pondering the links between her job and her presence here, as well as the ethos.

“It’s about connection,” she said about why she had come here. “It’s about autonomy and self-expression.”

Regina, a 36-year-old who is also a project manager at another startup, wore a Raggedy Ann costume and declared that it was easy to judge a place like Mission Control.

“It takes someone educated and sophisticated to build a place like this. It takes maturity,” she said. “These are our kind of people — professional, young, smart. Can you just talk to anyone about non-monogamy? Not really.”

Enough chitchat — it was time to head to the second floor, where it got a lot more serious. Walking up the stairs, one could hear the faint sound of slapping. There was a handwritten sign that said “Ask 1st” and then a poster with Fungeon — translation: fun dungeon — “Do’s and No’s.”

For example: Do greet the DM (dungeon master). Do keep your sound volume reasonable. Do watch from a respectable distance. No open flame or drawing blood.

It was here that Big Red worked as dungeon master, which sounds scary, but is basically a manners and consent referee for the melee. Unlike those in techie uniforms, he had one of his own: A red jock strap, tube socks, combat boots, and he carried a glowing baton.

A young man sauntered up carrying a nylon side satchel with a startup logo on it and wearing a bulldog harness over his t-shirt. Apparently, it was a freshman error: The harnesses are typically worn over bare skin, noted Big Red, who was wearing one, as well.

Nicki, a 30-year-old who lives on Nob Hill and just launched his tech company, wore slacks and a tuxedo shirt with a powder-blue tie. He asked Big Red how this whole sex party works, exactly: “Do I just tap on someone’s shoulder?”

There was a table in the middle of the room with candy necklaces, condoms, towels, a spray bottle of bleach and several rolls of paper towels. The decor was loosely harem-style. Mattresses with purple sheets lined up on the floor and gauzy red streamers hung from wall to wall. There was a pole in the middle of the room, as well as a life-size fertility goddess with red-tinseled scaffolding around her.

San Francisco State University adjunct instructor Michael Shannon had been the dungeon master a few weeks earlier when some attendees were talking about how they would use consumer electronics cords in sex play.

“If you’ve never tied [someone] up with an ethernet cable, you’re not geeky enough,” Shannon once opined to me, in one of the more interesting nerd tips out there.

(By the way, if you think about a lot of common tech terms, they can quickly get kind of naughty if you are in that frame of mind: Dongle, poke, keystroke, RAM, byte and, of course, megabyte. There are others, but you have to draw the line somewhere.)

Mission Control started during the first tech boom, when Whittaker came to San Francisco. Today, she said it shouldn’t surprise people that the club is growing.

“The whole time I’ve lived here, people have said, ‘Oh, the culture has been pushed out of San Francisco.’ Since 1999, the same thing,” she said. “But this city was built on a pioneering spirit. People came here to go as far as they could go.”

For many years, it operated out of a cavernous apartment in the Mission but, after it started the application for 501c7 status and the police came to a particularly rowdy party, Mission Control was evicted in December.

“Frankly, I am not sure what other permits might be required for this type of business,” wrote Deputy City Attorney Michael Weiss to the building’s property management group, after it was also shocked to discover the tenants.

In any case, the parties since their eviction have continued, and Whittaker is determined to find a permanent space to make room.

Back at the party, things were escalating — and getting a little too packed. The pile of costumes by the mattresses grew, the tinsel-wrapped scaffolding around the fertility goddess began to collapse, and Big Red, who is Mr. September 2014 on the annual for-charity Bare Chest Calendar, called for duct tape.

Nellie Bowles

Thus, it was time to head downstairs, where there was a show with burlesque dancers performing to “Sugar, Sugar.” Whittaker then took the stage.

“I’d like to explain to you all the difference between objectification and attraction,” she said, to loud cheers of the ever-growing crowd. Whittaker was wearing pink platform boots, a Little Bo Peep dress and a headpiece with plastic cupcakes.

It went on like that throughout the night, as it has been and will continue to.

James, a 25-year-old who recently left a large tech company to start his own, said in an earlier interview that people who work with code might build alternative relationships or have eccentric sex lives without intentionally rebelling against anything.

“Software engineers and tech people in general have an approach to figuring things out that is very logical and accidentally nonconformist,” he said. “It’s not that they want to break the rules, but they think the rules have no a priori reason for existing.”

He was still surprised that he recognized a lot of people his very first night at Mission Control.

“It’s a ton of software engineers,” James said, laughing a little. “Like a really awkward, nerdy crowd, which is a really funny thing for a sex party.”

[Clarification: The author of this story, Nellie Bowles, began work on a similar story to this one while employed at the San Francisco Chronicle. Reporting, writing and editing on the story was never completed, nor was the story ever published, during her employment there. She continued to work on the story after leaving her job, and disclosed all this to her Re/code editors when proposing the story. So, to avoid replication of her Chronicle work and once she was working at Re/code, she was directed to re-visit the club on a separate night and do fresh interviews, and she did so. However, in the case of some people in the piece, she merely asked if they stood by the quotes they had given her during her earlier reporting for the Chronicle and also after she left. They said they did, so their quotes are the same as those in a never published draft. We regret that we did not ensure that all parts of the story, including all quotes, were fresh, and have reflected all places where earlier interviews took place. The Chronicle has republished this piece from Re/codehere, including adding photos taken by them at a different and earlier Mission Control party in another location.]

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